The present invention relates to a circuit arrangement for a motor vehicle having an ultrasonic sensor and an evaluation circuit to determine the distance of a motor vehicle from an obstacle. A circuit arrangement for the determination and display of the undershooting of predetermined minimum distances between a vehicle and an obstacle is already known from EP 48 958 B1. In the circuit arrangement, used as a parking aid, an ultrasonic sensor transmits sound waves and measures the transit time of the echo reflected from an obstacle. In this arrangement, the measurement of the distance from the obstacle is sufficiently precise only during the approach to an obstacle as far as to a specific minimum value, since the sensor cannot register every contour in the case of a very small distance from obstacles, for example from the fender of the vehicle. This leads to the measurement being aborted or no longer displayed, on safety grounds, at a distance of a few centimeters. In practice, this leads to a relatively large amount of parking space being wasted during parking.